What can I say?
OK, so I'm not that close to God!
That's a Clair Bros. 700 on the bottom missing it's Face Plate.
(... hey, if anyone has a spare 700 Series 2 face, let me know, PLEASE)
There's one behind it too, but at least it's complete and almost mint. (best place for it)
Both 700's operate into 4 ohm loads and always have with no ill effect.
That's a 400 in the middle and then a 200, and then a 5100 Tuner.
The 4000 pre-amp is on the other side of the unit, along with an Amcron EQ2.
Speakers are 4x 2215's in 4530's and a pair of 10 cubic foot ported boxes, and 2421's (yes, I know, should be 2440's but at AU$800pr that ain't gonna happen too soon), plus adaptors on 2309's with 2310 lenses plus 077's all crossed with Crown VFX2A's and a FFX2.
I'm also using 4x 10" speakers from my L40's and L36's for the lo-mids.
For what it is, it's incredibly quiet, and I don't realise it's on most of the time, until the power bill comes around.
As far as popping any of my PL's are concerned, haven't had any problems with daily use for the last 10 years. (... touch wood!)
The Luxman LV103 on the top is on my 4301's. Very nice combo.
It's really just repaired stuff from a pile of rubbish, but it's all I got.
Cheers all.
I might be deaf, but I can still hear da bells! (Quasimodo)
.... Oh, and the Kick Drum.
A friend of mine still has his
Regards, Ron
JBL Pro for home use!
With a fan Yes: per the original owners manual (install 8 amp fuses)
The thing about this amp was its threshold of clipping into 8 ohms was around 450 watts into 8 ohms and 700 into 4 ohms. That was the whole point of the design and high damping factor like 1000 : 1 to drive the ART LST and other relatively low sensitivity loudspeakes. The advent of high voltage transisters used in TV HT power supplies made the 700B a reality.
http://images.google.com.au/images?h...title&resnum=4
Obviously efficiency goes to hell into 4 ohms in a linear amplifier (with such high supply rails) . The problem with 4 ohms is the losses with such high currents and high power levels and the heat. Most of the class leading super amps can now approach 6 fold those numbers into 8 ohms and down to 2 ohms with switchmode PS. The point is a dyanmic range from an amp that can put out such large voltage swings.
http://www.labgruppen.com/downloads/...LM14000_V3.pdf
The Crown amps of that era could not do that and only then in bridge mode.
It must be remembered that we're talking about amps that are 40+ years old don't forget.
These were the first of the 'Super-Amps' and were at the forefront of technology for the times.
It was a HUGE transition going from reasonably low powered Valve/Tube amps to these Solid State high powered devices.
I think the Crown DC300 came just before the Phase Linear 700, (correct me if I'm wrong), and there wasn't much more about except for maybe the BGW's which came a little later.
(... feel free to add to that list, IF you're old enough!)
Some have said that they don't remember seeing these in 'action' but there were companies about during the 70's and 80's, eg Clair Bros, USA, that must have had a thousand PL's for their huge Concert Touring Rigs.
You may not have seen them, but you certainly heard them.
.... but then again, this only applies to those from THAT era that were out and about at the time.
Some companies used PL's, and some used Crowns.
Same as recording studios.
It was always one or the other, but the one thing most had in common were JBL monitors. A match made in heaven regardless of which amp you used.
We have so much to be grateful for to these two Audio Co's as we wouldn't have some of the most exotic stuff today without their, (PL & C's), pioneering R&D and productivity.
I mentioned before I have a heap of PL's. I'm now starting up a similar Crown set-up. Again from 'found' broken bits.
I don't necessarily prefer one over the other. I love both.
They both have their problems, but there's so many solutions available on the 'net these days, that not having a perfectly working unit is no excuse really.
Anyway, whichever you have, enjoy it/them.
Cheers all.
I might be deaf, but I can still hear da bells! (Quasimodo)
.... Oh, and the Kick Drum.
Agreed,
Has anyone heard of SAE.
I repaired a 50/50 watt SAE power amp about 18 months ago and it was really nice. I replaced most of the transisters including the drivers with original types (darlington outputs) and used more modern low noise true equivalents for the Dual input Diff pairs and matched the HFE. Some capacitors were also past their used by date.
That made a hugh difference from being just another amp to the dizzy heights of a Levinson. Its surprising how different a transister can sound with the same spec. When match with the optimum HFE it can be night and day in terms of resolution and tonal balance. In this amp the previous repairer put in odd types (probably from another repair) so it was a sick puppy for a long time. Now I get a free beer whenever I see the owner!
I think SAE man has a big stash of those.
The point of this post is that if you buy an old Phase Linear it probably wont sound as good as new and even less likely to be working properly if it had been blown up.
Absolutely spot on Ian....
I think anyone reading this can apply what you said to just about any of the BIG amps of the time.
So the best advice for possible future purchasers of any VINTAGE amp, go over it first before you power it up.
... and as Ian already mentioned, replace a few of the essential bits, eg, make sure all the transistors are matching and working, and chuck out any capacitors in the signal path and replace with the better stuff available today, and be prepared to have the biggest grin on your dial for a good length of time.
SAE stuff was good too I thought. On par with the big ALTEC amps.
I think I'll go and have a nap now....
I might be deaf, but I can still hear da bells! (Quasimodo)
.... Oh, and the Kick Drum.
This question always draws out the naysayers. Gotta laugh. Yes it's true, if you load up a Phase Linear model 700 with a stout 4 ohm load and pour the coals to it - it will indeed go China Syndrome and in relatively short order. I guarantee it.
Now, is it the amp or the user? Not to bash here. It's already been posted the owners manual mentions cooling fans being necessary for high power applications. They are.
Lots of air and air exchange - cool air. I always use 200+ CFM of fans (2 x 100 cfm) on the 700's in commercial use. And ensure the air in the rack circulates properly.
Companies like Audio Analysts, Heil Sound, and Clair Brothers Audio used Phase Linear amps back in the day for many years. That fact speaks volumes about the amps and how robust they are/were.
I used 400's, 700's and 300's in pro sound, disco's and my home system for many years. 3 clubs running 700's through the 80's open 7 nights a week and I had 2 amp failures from the 700's and 1 failure with a 300. Also had 2 portable systems running - one for DJ and one for club bands.
Tore up a few JBL E-120 12" 16 ohm low mids and a few E-155 8 ohm 18's with the 700's until I learned to correctly calobrate the gain structure in the systems with the old Ashly limiters and crossovers.
What I'm saying is they are flamethrower amps and about as reliable as any if properly setup.
For home use, 12v 120mm whisper fans work pretty well - depending upon how hard the amp is pushed at 4 ohms and for how long.
About the only thing one can grip about for these amps is the fan noise needed to push enough air across them to prevent amp failure.
Sorry for the late reply...but one of our clients used 700's exclusively many (30+)years ago. They had BiPolar 140v power supplies and could swing some current...but no protection.
Not to say DC300's didnt have issues..but most were due to crappy equalisers or poor stage habits. A Soundcraftsman EQ would put out DC on turn on...or when the cord was plugged back into the wall (after being kicked out). Not the Crowns fault but it would smoke the drivers every time.
I once came across some McIntosh amplifiers because the guy liked the phase linears better. I was happy, got some Mc's
He fired the PL on some altec A7's and it did sound good man...
the first amplifier i recall as being 100wpc and over, or (then) "super-amp" material was the Mattes SSP200, a 100 wpc pwer amplifier. i believe within a year of it's release Mattes produced the SSA 200 which was an integrated amplifier. I owned an SSA200 and ran a pair of Altec-Lansing Flamenco's (see Bogator's avatar). It was a very good-looking piece of equipment, with a very coplex control panel. I haven't been able to find a picture of any Mattes components online, and even mention of it is hard to come by. there is some discussion at this link.
http://www.audiokarma.org/forums/arc...p/t-25298.html
and roger russel of mcintosh fame also has a review of one for sale at
http://www.roger-russell.com/magrevhf.htm
Hi guys, seeing this thread brought back some memories, some good, some bad about my much loved (back then at least ) PL 700.
A friend at the time was importing some nice American kit to the UK, and having compared his then set up, of a Crown IC 150, driving a PL 700 into Bose 901's , to my Quad set up (brand, not the 4 channel audio of the era) I fell in love with it!
A short time later, I had my own PL 700 and original Bose 901's, and thought there was nothing to compare with it.
Except one day, returning from holiday, I switched it on, and was aware that only one channel was working, long story short, it had gone dc, and take with it one of my 901's ( 9 drivers!)
The then UK distributor very kindly swapped the amp for a brand new unit, and I bought replacement drivers for the Bose.
This combination lasted for a while, but then, just like history repeating itself, one channel went awol, and I decided my love affair with the PL had come to an end.
When they worked they were amazing, when they didn't, they cost you money!
Ain't that the truth?
I've still got 2x 700 II's, a 400 II, and a 200 II on my 'stereo' which hasn't been turned on for almost a year after being used daily for ten years, and now I'm just too scared to turn the sucker on!
I could pull 'em all out and go over them, but I just can't be bothered anymore. Maybe one day....
So, I use my Crown stereo instead for now, which has been in constant reliable use for ages.
.... but I do miss the PL's. Nothin' like a bit of headroom to spare!
Cheers.
I might be deaf, but I can still hear da bells! (Quasimodo)
.... Oh, and the Kick Drum.
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